It's not you. You just have to listen to what they're saying. You might walk into a room and hear "God damn arab". It's NOT directed at you. The remark is directed AT the torrorists. Unfortunately it is natural for people to lash out like that, it helps them ease the shock, pain, and anger surrounding the incident. They're only letting off steam. By having the appearance of an Arab, you are an easy target, but it's not you who they hate.
Don't take this the wrong way, but they're looking at you and seeing the face of Osama Bin Laden, not your face. So take it lightly and dismiss it as a remark inteneded for someone else. Don't let it get to you. Once we and the world show Osama who's boss, things will cool off.